News & Events

August 19th, 2005

Environmental engineers study pollution of Colorado mountain streams by mines

Diane McKnight (INSTAAR & CEAE) and Jeff Wong (CEAE) spoke with KUNC's Gavin McMeeking about the pervasive pollution of Colorado mountain streams by mining and the potential for remediation by environmental engineers. More than 19,000 abandoned mines in Colorado have polluted more than 7500 miles of streams (equal to the distance from Los Angeles to Sydney Australia). This summer McKnight and Wong are concentrating on Peru Creek in Summit County (Snake River Watershed). The creek's bed near an abandoned mine is covered by metal oxides at a level that prevents algal growth and is lethal to aquatic life. There are no stream insects and thus, no fish and riparian birds.

To help understand the transport of metals, Wong set up a salt injection tracer experiment that mimics the behavior of some non-reactive solutes, such as zinc, and helps in quantifying how much iron oxide is being deposited. Undergraduate students in the CU Biomathematics Scholars program based at INSTAAR participated in the downstream sample collection. Computer modelling of the experiment's data will provide ideas for remediation, but much remains to be learned and eventually millions of dollars will be needed to clean up this stream and many others.

Ironically, another hurdle to successful remediation is the Clean Water Act, which mandates that any group working on remediation becomes liable for the environmental damage. Congressman Mark Udall has proposed a "good samaritan" amendment but it has stalled in Congress.

Two other INSTAAR grad students, Andrew Todd and Chi Yang (CEAE), are studying the combined effects of limited prey and metal toxicity on fish and birds in other less severely impacted stream reaches in the larger Snake River Watershed.

The interview aired on KUNC: 91.5 Community Radio for Northern Colorado on August 4, 2005.